Production of metallic compounds of dyestuffs



Patented New. 22 1928.

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I name xnzixanna, on Mannnnnu, an]: wnnnna marina, on nnnwresnannn-on THE-RHINE, GERMANY, ASSIGNORS- TO GRASSELLI DYESILUW CQREUEATJIQN, @E NEW YORK, N. 32., A CORPORATION OF DELAWARE.

PRODUCTION OF METALLIC COMPOUNDS OF DYESTUEE'S.

No Drawing. Application filed April 1, 1927, Serial No 180334; and in Germany June 15, W28.

' If dyestuffs, which are capable of forming complex metallic compounds but are diifioultly soluble or insoluble in water, be treated with aqueous solutions of suitable metallic compounds, the complex metallic compounds are formed only in a very incomplete manner, if at all.

We have now found that the formation of 'the complex metallic compounds of the dyestufi's takes place very smoothly and .completely when the reaction is allowed to take place in the presence of such organic solvents, as are more or less readily soluble in water under the prevailing conditions and are capable of dissolving the dyes-"studs. In other respects, the action of the metallic compounds on the dyestufis may take place in any convenient manner, as for example, with or without the application of pressure and the like. Typical solvents for use according to this invention are monoor polyvalent alcohols, such as methyl-, ethyl-, propyl-, butylalcohols, and the like, glycol and its ethers or esters, polyglycol and glycerol; also ethylenechlorhydrin, triethanolamine, 'thiodiglycol, phenols, acetone and other ketones, and the like. Mixtures of organic solvents may also be employed.

The following examples will further illustrate how the said invention may be carried into practical effect but the invention is not limited thereto.

' Example 1.

28 parts byweight of the azo dyestufi obtainable from the diazo compound of p-chloro amin ophenol and ,B-naphthol are heated in an autoclave with about 400parts by volume of ethyl alcohol and 120 parts by Weight of an aqueous solution containin 7.6 parts of chromic oxid and 13.5 partsiy weightpf 85 per cent formic acid, for about 3 hours at 120 C. The resulting, partially dissolved dyestuff is precipitated by the addition of water, or by distilling off the alcohol, and is filtered by suction and washed. On drying, a violet dyestufi is obtained, the alcoholic solutionof which does not change color on the addition of alkali; If an attempt be made to produce the same .chromiferous dyestutf in water,

under otherwise equal conditions, a large proportion of the original dyestud remains unaltered.

Example 2..

32 parts by Weight of the azo dyestufi' obtainable from the diazo compound of p-chloro-aminophenol and 3-methyl-l-phenyl-5-pyrazolo-ne are heated at 120 C. in an autoclave, for about 3 to 4 hours, with r00 parts by volume of ethyl alcohol and the same solution of chromium formate as specified in Example 1. The red chromium compound of the dyestutl is obtained on adding water to the reaction mixture.

A mixture of methylandbenzyl-alcohol for example, may be substituted for the ethyl alcohol in carrying out the process.

We claim p y 1. The process of producing metallic compounds of such dyestufi's as are dificultly sol- -uble in Water which consists in treating such a dyestuff with an aqueous solution of a metallic compound capable of reacting therewith in the presence of an organic solvent ca able of dissolving the dyestufi and miscib e with water.

2. The process of producing metallic compounds of suchdyestufi's as are dificultly soluble in water which consists in treating such a dyestufi with an aqueous solution of a metallic compound capable of reacting therewith in the presence of, a water-soluble aliphatic alcohol.

3. The process of producing chromium compounds of such dyestufi's as are dificultly soluble in water which consists in'treating such a dyestufi' with an aqueous solution of a chromium compound capable of reacting therewith in the presence of an or anic solvent capable of dissolving the dyestu and miscible with water.

In testimony whereof we have hereunto set our hands.

HANS KltZIKALLA. WERNER MER. 

